Who sold them? Were you together? How much does a license cost?
>I need 500 by next Tuesday to convince my CTO to build an MVP.
Why 500? Why not 10, 235, 499, or 357?
Why Tuesday? Why not Monday or Thursday?
What are your constraints?
This seems like a strategic decision and your product/mock-up should solve that... Have you used your own product to solve it?
We sold the 100 licenses together. A license costs $1/month per user now instead of $6.99/month per user.
The 500 licenses and Tuesday are my CTO's requests. He will build the tool when I can deliver the licenses by Tuesday.
And yes, our product should solve the decision making part of this problem but, it may not help me getting 500 licenses :-)
Saying it integrates with those other services is a lie?
I think this is a silly.
It sounds like 'an ideas guy' built a landing page quickly, and collected some email address from that fake try-now page. And is now trying to convince a developer somewhere ("the CTO") that is a good idea and worth building for them.
They are not your cofounder/CTO if they need convincing like this.
1. Convince the executive team of why this is a worthy problem to solve. The only business impact any product can have is acquiring new users (new revenue), increase deal sizes with existing customers (expansion revenue with monetization), minimizing customers churning (retention revenue).
2. Clearly answer why you need to focus here now. Associate your proposal to a compelling trend that is relevant for your business.
ROI is key here. Sounds like you have traction you just need to tie it to an existing important business outcome your company already cares about. I have also done and currently doing intrapeneuriship and this is how I have been successful in getting ideas funded and brought to market. The best ideas usually are increasing revenue through monetization, it's usually less risky than pitching to acquire new customers.
Your company has existing goals, revenue projections, hiring plans, budget allocation, headcount allocation, etc that all of your company leaders have agreed on.
Asking to build an MVP requires not only the cost (budget, headcount, etc) to build and launch the MVP, but also an opportunity cost as less resources are being used towards the existing plans.
When I've worked on new businesses, we first get buy in from the top execs, but the next step is to work with finance on budget and revenue projections, and with departmental VPs on finding headcount to join the new team.
This might be a lighter weight process in a smaller company, but my point is that it's not just your CTOs approval you need, though your CTO could be your champion to help persuade everyone else this is worth doing.
I wouldn't put a deadline on the 500, though.